MYH14 and cardiomyopathy: These results suggest that increased RLC-phosphorylation in PPP1R12Bf/f/Cre+ mice prompts myosin cross-bridges to enter the DRX state to interact with thin filaments and produce force and muscle contraction, the phenomenon previously observed in pseudo-phosphorylated RLC (S15D-RLC) reconstituted LVPM from cardiomyopathy mice (51, 52).